6VPE supports VPN connectivity over an MPLS IPv4 provider core network. This feature is very similar to 6PE, but the main difference is that the system uses VRF tables for forwarding lookups at the PE and uses VPN address-families in BGP.
Upon receiving IPv6 traffic from one customer site, the ingress PE router uses MPLS to tunnel IPv6 VPN packets over the backbone toward the egress PE router identified as the BGP next hop. The ingress PE router typically prepends the IPv6 packets with the outer and inner labels before putting the packet on the egress interface. At the MPLS penultimate hop label popping, the remaining BGP label identifies the egress PE interface toward the customer site. It also hides the protocol version (IPv6) from the last P router, which would otherwise need to forward an IPv6 packet. A P router is ignorant about IPv6 VPN routes. The IPv6 header remains hidden under one or more MPLS labels.
You can use the ping6 and traceroute6 commands to validate data-plane connectivity and to detect any blackholing of traffic. In addition, you can use the show forwarding ipv6 route command and regular MPLS commands for troubleshooting.
External and Internal Border Gateway Protocol (EIBGP) is supported for 6VPE, and it functions like the equivalent IPv4 L3 VPN feature.
See Part 5 of this guide for more information about Layer 3 VPNs and 6VPEs.
